Screw-pump.



E. S. BENNETT.

SCREW PUMP.

APPLIUATION FILED AU'G. 28,.1908. RENEWED JULY 21, 1909.

Patented Mar. 1, 1910.

UNITED STA. PATENT OFFICE. I

ERASTUS S. BENNETT, OF NEW .YORK, N. Y., ASSIGNOR T0 CONTINENTAL ENGINEERING COMPANY, OF NEW YORK, N. Y.

Specification or Letters Patent.

SCREW-PUMP.

Application liled August 28,1908, SeriaLNo. 450,707. Renewed July. 21, 1909. Serial Ho.508 ,785.;

To all whom it may concern:

Be it known that I, Enis'ros S. Bnnnnrr, a citizen of the United States, residing at New York, N. Y., have invented certain new and useful Improvements in Screw- Pumps, of which the following as a specificatlon.

- My in'ventionrelates to screw pumps of the general form disclosed in an application for Letters Patent of the United States filed by me April (3, 1908, No. 425502. In said application I disclose a pump comprismg a cylinder having a plurality of inlet openings in one of its headsand a plurality of outlet openings in the otherhead, ascrew within the cylinder having a plurality of i threads which are displaced circumferen-' tially in respect toeach other, one thread acting in connection with one inlet and outlet, while simultaneously the other thread acts in connectionwith the other inlet and outlet, the ends of the screw threads work longitudinally through the ---pump. Fig. 2.

- is a vertical sectional view taken transversely through the pump on the line 2--2. Fig. 3 is a cross sectional view on the line 3--3 of Fig, 1. Fig. 4 is a face View of one of the inlet or outlet openings, of the pump.

'Fig. 5 is a face view of one of the dia in a casing 6, formed or-castwith the cylina web 7 exder head, the said inlet havin tending across the same divi mg'the inlet" into two openings 8- and 9, which lead to the are shaped inlet openings lO'and 11 of openings in the cylinder head, together with with one of the inlet openings, while the other screw blade is simultaneously acting in connection with theotherinlet opening, both blades working close against the inner face of-the head of the cylinder and servin to force the water longitudinally of the cy index to the discharge end. The discharge the outlet pipe from the casing are counter- Patented Mar. 1, 1910. y

arranged that one is acting in connection parts of the arc-shaped inlet openings'lQ and 11 and the inlet 6,

In order to prevent the back drag of the water which results from the skin friction existing between the surface of the screw blade and the body of water, I provide means whereby the body of water having been forced longitudinally of the cylinder will be separated from the screw blade'which 4 has propelled it so that it will be relieved of the skin friction and may be acted on anew by a second blade forming in efiect a continuation of the first blade section. These means consist of a diaphragm 19. secured to the cylinder oftthe pump and extendingtransversely across the same, it having a central opening for the passage of the shaftand having a plurality of openings 12 and 13, the aggregated area of which is approximately equal to the aggregated areaof the inlet openings 10 and 11 or of the discharge openmgs leading from the pump.

This diaphragm or diaphragms may be secured in place in any suitable manner. I have shown, however, screws atl l, passing through the easing into the said diaphragm. It will be seen from Fig.1 that each of the screw blades =l-5 works closely against both the inner surface of the head of the cylinder and against the face of the diaphragm 12 so that in the revolution of the screw the blades will cut ofi the water at the inlet openings and press this cutoff portion forward through the openings in the diaphragm, and imme lately upon ts assage through the diaphragm the effect of skin friction will be eliminatedand the body of water which has just passed through the diaphragm will be subjected to the action of the next section of screw blades and so on throughout the cylinder. v j

It will be noticed from Fig. 1 that the sec tions of the blade 4 form in effect a continuous screw from end ta ent! of the cylinder,

' the axis of the blade.

'the diaphragms as it were occupying the the same, a plurality of inlet openings in one head, a'plurality of outlet openings in the other head, a screw within the cylinder having a plurality of threads displaced circumferentially in --respect to each other, one thread acting in connection with one inlet vand outlet while simultaneously the other.

thread acts in connection with the other inlet, and outlet, and a diaphragm extending transversely of the cylinder and between the sections of the screw threads which work closely thereagainst, said diaphragm having openings aggregating in area the area of the plurality of in et openings or outlet open- I ings, substantially as described.

-2. In combination in a screw pump, a cylinder, a shaft extending "therethrough, a screw thread on said shaft, a diaphragm extending transversely of the cylinder, and be- 5 tween the sections of the screw, which sections work closely against the face of the diaphragm, said screw also working closely outlet, and a screw working within the cyl-' mder on each slde of the diaphragm, the

thread on one side of the diaphragm forming practically a continuation of the thread upon the, other side of the diaphragm, said thread working closely against the diaphragm. substantially as described.

4. In combination in a screw pump, acylinder haw-'ing an inlet'and an outlet, a helically bladed member arranged to rotate therein and a perforated diaphragm inserted in the said helical blade, substantially as described. I

- In testimony whereof,I aflix ny signature in presence of two witnesses.

ERAST US S. ,BENNETT.

\Vitness'es:

G120. H. LIGHTFOOT, M. L. JUSTIN. 

